1. Field
The invention is in the field of athletic shoes having soles provided with air cushions.
2. State of the Art
It has been generally recognized for many years that certain athletic events, in particular those involving a good deal of running or walking, can result in tiring and even long term damage to the feet of participants. As a result, shoes with various types of soles have been devised to reduce the impact on the foot when the shoe strikes the ground or other playing surface. Usually these have included the insertion in the sole of some form of resilient compressive material which reduces the peak pressure experienced by the foot as the energy of the impact is absorbed. In some shoes, air has been employed to augment the cushioning, usually involving means whereby the air can be successively and alternately exchanged between inner portions of the sole and the external atmosphere.
However, existing shoes of this type do not effectively optimize cushioning of the impact on the most affected parts of the foot, namely the tuberosity of the calcaneous in the heel region and the heads of the metatarsal bones in the forefoot region.